616
FXUS62 KRAH 191732
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
130 PM EDT Sun May 19 2024

.SYNOPSIS...
High pressure will extend across and offshore the Middle Atlantic
through Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 920 AM Sunday...

With the morning update, made some minimal changes to hourly
temperatures and dewpoints. Radar echoes over the forecast area have
decreased significantly in the last hour, and didn`t extend the
drizzle that was in the forecast through 9am. That being said, think
there could still be some light showers across the southern tier of
the forecast area during the afternoon, although removed the chance
pops from Sampson County. No thunder is in the forecast considering
the stable atmosphere. Clouds should be slow to clear today, and
didn`t make any changes to that part of the forecast either.
Previous discussion follows.


As of 355 AM Sunday...

A positive tilt mid/upr-level trough will move across and offshore
the Middle and South Atlantic through tonight. The most prominent
shortwave perturbation, evident as a compact cyclone over wrn TN in
the 00Z 250 mb upr air chart last evening, will move from the TN
Valley this morning to the GA/SC this afternoon. While height falls
and forcing for ascent will be maximized along the track of that
feature (ie. south of cntl NC), a weaker disturbance now over MD
will move south and across VA/NC through 00Z Mon.

At the surface, a cold front now draped from sern NC wwd across n-
cntl SC will continue to make steady progress swd and across SC and
the Savannah Basin today. Ridging over the Middle Atlantic will
follow and extend across NC with associated nely flow.

Widespread low overcast that has developed in the post-frontal, nely
low-level flow regime over cntl NC will lift and scatter to partly
to variably cloudy from northwest to southeast this afternoon-
evening. While the focus for light measurable rain will result over
far srn NC this morning, near and north of the aforementioned cold
front, the weak disturbance approaching from MD/VA may result in the
development of a few very light showers/sprinkles over the ne
Piedmont and Coastal Plain this afternoon.

Continued clearing skies this evening-early tonight will result in
the development of radiation fog and stratus later tonight-Mon
morning.

Temperatures and dewpoints will be 5-10 F lower than Sat on average,
with highs mostly 70-75 and lows in the 50s to around 60.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
As of 341 AM Sunday...

Under mid-level ridging, cool nely flow will continue on Monday as
high pressure extends down the eastern seaboard. Dry weather is
expected with some continuation of stratocu likely through the early
evening. Low-level thicknesses will rebound a bit compared to
Sunday, but temperatures will still top out a few degrees below
normal in the mid to upper 70s.  Dry weather and cooler overnight
lows in the mid 50s is expected.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 341 AM Sunday...

Upper pattern through the extended: Mid-level ridging will largely
hold over the eastern US before shifting offshore through Wednesday
evening. The next series of upper troughs will then lift through the
Great Lakes Thursday and potentially the TN Valley on
Friday/Saturday.

Tuesday through Wednesday: By Tuesday, the air mass will start to
moderate some as flow turns a bit more ely, and then sely/swly
Wednesday into Thursday.  However, overall Tuesday and Wednesday
should be dry with temperatures warming into the lower to mid 80s.

Thursday through Saturday.  Ensembles continue to suggest the
potential for periods of rain over this time as upper forcing from
the aforementioned upper features move overhead. On Thursday, an
upper trough will lift through the Great Lakes. Some mid-level
energy associated with this feature may trickle down into our
northern locations and promote showers/storms later in the day.
However, the better forcing and low-level moisture transport appears
to stay well to our north, and thus as of now will maintain just
slight chance to low chance POPs during this time.

From Friday onward, there is a bit better agreement amongst
ensembles simulating a potentially potent short wave riding through
the TN Valley and eventually over central NC through Saturday. Still
a bit far out to get into specifics, but This setup could provide a
bit better coverage in showers/storms for our area early this
weekend.

There is high probabilities amongst ensembles that temperatures will
exceed the mid 80s both Thursday and Friday.  The quartile spread
widens a bit more over the weekend, likely due to differing
solutions wrt to any sfc boundaries. Regardless, temps will likely
remain in the 80s this upcoming weekend.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...

24 hour TAF period: Widespread stratocumulus will continue to lift
and scatter out, with all terminals expected to return to VFR
conditions by late afternoon. There is high confidence in skies
becoming mostly clear during the evening, but with little change in
air mass, restrictions are expected to develop after midnight. Have
made little change to the inherited TAFs through this part of the
forecast. Believe that the greatest coverage of stratus will be at
RWI considering the (light) northeast flow, and will go with IFR
stratus there. At GSO/RDU, winds will likely go calm, and models are
showing a very shallow yet strong inversion, which should favor
IFR/LIFR visibilities. Considered going LIFR at INT, but did not see
as strong of an inversion signal there. Finally, at FAY, there
should be less moisture overall, and have not gone with any
restrictions. Fog/stratus should begin to mix out by the middle of
Monday morning, with VFR diurnal cumulus forecast for the rest of
the TAF period.

Outlook: A repeat of Monday morning`s restrictions will be possible
Tuesday morning, but this threat should not be as great for
Wednesday morning. Thursday and Friday will have the potential for
diurnally driven showers/thunderstorms.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...MWS
NEAR TERM...Green/MWS
SHORT TERM...Luchetti
LONG TERM...Luchetti
AVIATION...Green